Project Abstract Blood pressure (BP) control is one of the key strategies to help prevent cardiovascular disease (CVD). Conventional cuff-based, BP measurement in the clinic has not fundamentally changed in over 100 years, requiring significant time and effort per measurement for both clinical personnel and the patient, while also being unable to catch transient BP fluctuations. Current ambulatory blood pressure monitoring (ABPM) technologies are based on the same (cuff-based) principles and hence remain obtrusive, require excessive time per measurement and are unable to catch transient BP fluctuations. Our previous work suggests that the superficial temporal artery (STA) tonometry is an optimal approach for wearable, unobtrusive BP monitoring: it is suitable for long-duration use, can be built into a small form-factor, can provide continuous waveform measurements of BP, and is compatible with the latest electronic health records (EHR) and information technologies. As with other non-invasive, cuffless BP technologies, however, STA tonometry suffers from significant calibration challenges. The goal of this R21 project is to develop a wearable BP monitoring module, and investigate and integrate two novel approaches to improve the calibration of STA tonometry: multi-sensor STA tonometry modeling, and adaptive correction of hold-down pressure drift. To make the STA tonometry approach more clinically viable, our goal will be to extend the required calibration interval to at least 4 hours. We will conduct validation studies against gold-standard continuous BP monitoring systems, and also conduct a feasibility study of wearable long-term (12-hour) monitoring using dual-sensor STA tonometry, applying our combined calibration approaches. Stable STA tonometry BP measurements will provide a revolutionary step forward from the current 100-year-old BP measurement standard, and will facilitate major improvements in health management for people who suffer from symptoms and risks of CVD.